In U.S. Pat. No. 5,609,759, and in co-pending applications Ser. No. 09/008,845, filed Jan. 20, 1998 and Ser. No. 09/132,312, filed Aug. 11, 1998 (the disclosures of which are hereby incorporated by reference herein) a wide variety of different types of filter assemblies are described which have great portability, are inexpensive, and are capable of removing a significant amount of chlorine, and/or other undesirable contaminants from water, both to improve the taste and in some cases to improve the safety of the water for drinking purposes. The basic concepts disclosed in this patent and co-pending applications are becoming increasingly popular, and demonstrate that there are even a wide variety of other potential uses for the basic filtering assembly if appropriately simple yet effective constructions can be devised.
According to the present invention, various filter assembly constructions are provided which expand the versatility and functionality of the basic concepts of the filter assembly disclosed in the above-referenced patent and co-pending applications. The filter assembly constructions according to the present invention are capable of providing, according to one aspect thereof, a portable water treatment unit which has the capacity to remove at least 50% of each of lead, arsenic, bacteria, and/or viruses, or like contaminants, as well as chlorine, taste and odor. Though the construction according to this aspect of the invention is not much more complicated than the construction in U.S. Pat. No. 5,609,759, it has greatly enhanced functionality. These desired results may be achieved by providing an axial flow pathway for treatment of water before it flows into a substantially annular cavity surrounding a conventional primarily radially flow filter element (such as a porous activated carbon and plastic matrix having a porosity of between about 10-150), or a micro-porous filter element, which maybe in a pleated or accordion configuration, is provided through which liquid radially flows to the inner filter element. Alternatively, the treatment of the liquid may be provided by cooling the liquid, to improve its taste and the effect is has on the user, a water chilling element being provided defining the substantially annular open cavity and cooling the water and flowing into and within the cavity.
According to one aspect of the present invention a filter assembly is provided for use with a bottle having a substantially circular cross-section neck or open end. The filter assembly comprises the following components: A cap for closing the bottle neck or open end, including an upper surface. A manual valve, manually movable between open and closed positions, associated with the upper surface. An outer, substantially liquid impermeable, housing having upper and lower end portions, the upper end portion operatively connected to the cap. A plurality of openings in the outer housing disposed adjacent the upper end portion to allow liquid to flow therethrough. An inner at least primarily radial flow filter element having top and bottom ends, the top end operatively connected to the cap and positioned so that liquid from the bottle must flow therethrough before passing through the manual valve. A substantially annular open cavity substantially radially surrounding the inner filter element, and interior of the outer housing. And, a treating element which treats liquid passing through the outer housing openings and into the open cavity, the treating element operatively between the outer housing and the open cavity. The valve may alternatively be operated semi-automatically or automatically.
In one construction according to this aspect, the filter assembly further comprises an inner substantially liquid impermeable housing disposed between the outer housing and the inner filter and defining at least a majority of the annular open cavity, and further defining with the outer housing an axially extending substantially annular volume. The treating element may comprise a liquid permeable treating media disposed in the substantially annular volume and through which liquid must flow axially from the outer housing openings, past the inner substantially liquid impermeable housing, and then into the substantially annular open cavity. The inner housing outer wall, and the outer housing inner wall, which define the axial extending annular volume, preferably have an irregular contour, so as to minimize the chance of liquid channeling as it axially flows through the annular volume. For example the walls may be castellated or wavy. The treating element disposed in the annular volume preferably comprises a liquid porous media which is capable of removing of at least about 50% of at least one of lead, arsenic, bacteria, or viruses. For example the filter assembly may further comprise a retaining screen for the treatment media disposed between a lower end of the inner housing and the bottom end of the outer housing, and at the plurality of openings in the outer housing; and wherein the treatment media comprises granular or pelletized treatment media. For example the treatment media may be an ion exchange resin.
Preferably the filter assembly also further comprises a tubular mounting element extending from the upper surface of the cap down into the bottle in use and having inner and outer surfaces; and wherein the outer housing is releasably attached to the outer surface of the tubular mounting element in a substantially liquid tight manner; and wherein the inner filter element is releasably mounted by the inner surface of the tubular mounting element in a substantially liquid tight manner. In a preferred embodiment, the inner filter element comprises a carbon and plastic matrix having a porosity (pore size) of between nominally 10-150 microns and capable of removing at least about 50% (e.g. more than 70%, such as 90%+) of the chlorine and at least 50% (e.g. 90%+) of the lead in drinking water flowing therethrough, over a life of at least several (e.g. thirty) gallons.
According to another embodiment of the invention, the treating element comprises a substantially continuous at least primarily radial flow substantially annular outer filter element mounted within the outer housing to define the substantially annular open cavity as a first cavity adjacent an inner surface thereof, and to define a second substantially annular open cavity at an outer surface thereof, between the outer surface of the outer filter element and the outer housing, the plurality of openings in the outer housing communicating with the second substantially annular open cavity. Preferably the outer filter element comprises a micro-porous filter element connected to the outer housing in a substantially liquid tight manner at upper and lower ends thereof, so that water must flow through the micro-porous filter element from the second substantially annular open cavity to the first substantially annular open cavity. The micro-porous filter element may have a pleated or accordion configuration to maximize surface area, and may have a porosity of 3-6 microns.
According to another embodiment of the invention, the treating element comprises a water chilling element, and the outer housing is a thermal insulator over more than 80% of the extent thereof. Preferably the water chilling element is liquid impervious, and also defines a bottom cavity at the bottom end of the inner filter element.
According to another aspect of the present invention a filter assembly is provided for lowering the temperature of water in a bottle having a substantially circular cross-section neck, either the temperature of all of the water in the bottle at the same time, or defining a chilled volume so that the water is chilled substantially only before being filtered and passing out of the bottle. According to this aspect of the invention the filter assembly comprises the following components: A cap for closing the bottle neck or open end, including an upper surface. A manual valve, manually movable between open and closed positions, associated with the upper surface. An inner at least primarily radial flow filter element having top and bottom ends, the top end operatively connected to the cap and positioned so that liquid from the bottle must flow therethrough before passing through the manual valve. A water chilling element having a first end operatively connected to the cap, and radially surrounding the inner filter element, and surrounding the inner filter element at the bottom end thereof. And, the water chilling element defining a substantially annular open cavity substantially radially surrounding the inner filter element and interior of the water chilling element.
In this aspect of the invention, preferably the water chilling element is substantially liquid impermeable; and further comprises a plurality of substantially radially extending openings extending through the water chilling element to allow liquid to flow into the substantially annular open cavity. Desirably, the plurality of substantially radially extending openings are provided adjacent the first end of the water chilling element at substantially the closest portion thereof to the cap upper surface. Optionally, an insulating sleeve, substantially completely surrounding the water chilling element on the opposite side of the plurality of openings from the cap, is provided.
It is the primary object of the present invention to provide an effective, yet simple and compact, filter assembly capable of use with a bottle, and highly portable, and capable of treating drinking water in at least two different ways. This and other objects of the invention will become clear from an inspection of the detailed description of the invention, and from the appended claims.